研究分层页岩的剪切阻力和异构性
Min Gao1,2, Bin Gong3, Zhengzhao Liang4
1Engineering Research Center of Underground Mine Construction, Anhui University of Science and Technology, Huainan, P.R. China.
PloS one
|December 5, 2024
概括
在分层页岩中,切削强度是高度异质的,这是由于床层平面. 这项研究以数值方式研究剪切阻力,揭示了床铺方向如何影响岩石力学应用的强度和故障模式.
科学领域:
- 岩石机械学 岩石机械学
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 在岩石力学,特别是层状页岩中表征异构性,存在重大挑战.
- 床层平面对剪切负载下的页岩的异构强度和故障模式产生重大影响.
- 了解剪切断裂的产生和传播对于钻井和页岩气提取等各种工程应用至关重要.
研究的目的:
- 通过使用数值直接剪切测试,全面调查层状页岩的剪切阻力.
- 分析正常应力和床位平面定向对剪切参数的影响.
- 为了识别和描述层层的页岩中明显的剪断故障模式.
主要方法:
- 使用数值直接切削试验来模拟分层页岩上的切削负荷.
- 进行了正常应力和床铺平面方向的系统变化.
- 进行了切削强度,凝聚力和内部摩擦角的分析.
主要成果:
- 剪切参数 (强度,凝聚力,内部摩擦角) 受到正常应力和床位平面方向诱导的异型性显著影响.
- 剪切强度通常随着床位平面方向的增加而增加.
- 确定了三个主要的剪切故障模式:沿着床位平面,横跨床位平面,以及拉力和剪切故障的组合.
结论:
- 床铺平面的方向是控制分层页岩的剪切行为和强度的主要因素.
- 开发了三轴压缩下切削强度的实证公式和一个修改后的莫尔-库伦标准,以计算异构性.
- 这些发现为涉及层状岩石质量的工程实践提供了关键的见解,特别是在页岩气开采和地下施工中.
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